cache: don't check size if not necessary (#4140)

* cache: don't check size if not necessary

* Update lib/cache/sqlite-cache-store.js

---------

Co-authored-by: Matteo Collina <[email protected]>

Author: ronag

lib/cache/sqlite-cache-store.js

@@ -350,7 +350,7 @@ module.exports = class SqliteCacheStore {
   }
 
   #prune () {
-    if (this.size <= this.#maxCount) {
+    if (Number.isFinite(this.#maxCount) && this.size <= this.#maxCount) {
       return 0
     }